cobdray



(No Model.)

G. W. BLACKBURN 8e W. I. CORDRAY.

PUBNAGE eRATB. e

No.'325,651. 1 Patented Sept. 8, 1885.

We Z... mmrlll me l nun UNITED STATES FFiCE@ PATENT GEORGE XV. BLACKBURNAND TWILLIAM F. COBDRAY, OF COLUMBUS, OHIO; SAID CORDRAY ASSIGNOR TOHARRIET CORDRAY, OF SAME PLACE.

FU RNAC SPECIFICATION forming part of Letters Patent No. 325,651, datedSeptember 8, 1885.

Application filed March 22, 1884. (No model.)

To all whom it 11i/ay concern:

Be it known that we, GEORGE W. BLACK- BURN and WILLIAM F. CORDRAY,citizens of the United States, residing at Columbus, in the county ofFranklin and State of Ohio, have invented certain new and usefulImprovements in Furnace-Gratos, of which the following is aspecification, reference being had therein tothe accompanying drawings,in which- Figure 1 is a plan or top view of the grate. Fig. 2 is alongitudinal vertical section of the same. Fig. 3 is a perspective viewof the front tumble-bar. Fig. 4. is a side view of one of the tippinggrate-bars.

Our invention relates to improvements in furnace grate-bars; and theobjects of our in1- proveniente are to provide a furnace having a seriesof stationary grate-bars, made narrower at the fore end and curvedupward at the rear end, with one or more grate-bars provided with abearing in the middle of their length, and adapted to have their foreend tipped downward and again locked on the same level as the others. Weattain these objects by the construction illustrated in the accompanyingdrawings, in which- A represents the side wal ls, and A the bridgewall,of a furnace provided with the improved grate-bars B. Each of these barsis so formed that the upper face of its forward portion, I), (extendingabout one-half of the length of the grate-ban) is narrower than theupper face, b2, of the rear portion, so that the air-openings c in thefront end of the furnace are wider than the air-openings c2 in therearend. The draft is thus improved at the front of the furnace, where it ismost needed, time is saved in getting up steam, and the danger ofoverheating or blistering the boiler over the bridge-wall is obviated.

To protect the bridge-wall A against intense heat, and thus permitordinary bricks to be used in its construction, the rear portion, b2, ofeach grate-bar is gradually curved upward, and extends on alevel withthe top of the bridge-wall. The curve given to said rear portion, Z, issubstantially a segment of a circle, and permits a poker to follow thecurve, turn any clinkers upside down, and bring them forward to beeasily removed. The gratebars are supported at the rear end upon the Itransverse bars D and at the front upon the transverse bars D2.

To facilitate the removal of cinders, elinkers, dto., the two grate-barsB2 next to the last grate-bar on each side of the furnace areconstructed so as to have their forward -endeasily tipped downward. Forthis purpose they are provided, about the middle of their length, with asemi-cylindrical bearing, b3, in the under side thereof, to rest upontrunnions b4, projecting from theside ofthe two adjoining gratebars. (A.transverse bar extending across the ash-pit may be used in place of thetrunnions.)

The two tipping grate-bars B2 are connected at their fore end by atumble-bar, E, the ends of which enter mortises or recesses b5 in thesides of the bars B2.

To retain'the front end of the bars B2 on a level with the bars B, thereis projecting from the front of the tumble-bar E a lug, e, to rest upona spring-latcl1,f, passing through the front wall of the furnace. Thislatch is carried by a spring, F, secured to the front wall at f2, and isprovided with a handle, f3, at its upper end. The ends of both the latchf and the lug e of the tumble-bar are beveled, so as to readily passeach other when the grate-bars B2 are to be returned to their normalposition.

The grate-bars B and also are provided with the usual check-pieces orside projections, b5, at the ends and intermediate portions thereof, toprevent their warping and retain them at proper distances apart.

The rear half of the tipping grate-bars is slightly heavier than thefront portion; but when coal and clinlrers are piled upon said forwardportion it will have a tendency to tip down, and said motion is arrestedby a chain, C, having one end secured to the rear portion of thegrate-bar, and the other to the rear wall or to some other stationarypart. TWhen the bars have been relieved by the fireman of the coal andclinkers upon their front end, they will return to their normalhorizontal position either automatically or with the help of thefireman.

Having now fully described our invention, we claiml. The combination ofstationary grate-bars, having their rear portion curved upward andprovided with trunuions or their described equiva1ents,with thegrate-bars B2, connectingin the pivotcd grate-bars, substantially as andro bar E, having lug e, and the latch f, substanfor the purposedescribed.

tially as and for the purpose described. In testimony whereof we affixour signatures 2. The combination of stationary grate-bars, in presenceof two witnesses. 5 having their rear portion curved upward in GEORGEWV. BLACKBURN.

substantially the form of a segment of a circle, WM. F. CORDRAY. withsimi1ar1y-curved bars adapted to have Witnesses: their forward endtipped downward, and a con- C. C. SHEPHERD,

necting-bar having its ends entering recesses FREDERICK BUEHNE.

